基于深度强化学习的服务功能链可靠部署算法

针对当前关于服务功能链(SFC)的部署问题都未考虑到虚拟网络功能(VNF)的失效重要度，该文提出了基于深度强化学习的SFC可靠部署算法。首先建立VNF和虚拟链路可靠映射模型，为重要的VNF设置高可靠性需求，并通过链路部署长度限制尽可能保证虚拟链路可靠性需求。其次，以负载均衡为资源协调原则，与VNF可靠性联合优化，最终使用深度强化学习得到服务功能链部署策略。另外，提出了基于重要度的节点备份和链路备份策略，用于应对部署过程中VNF/链路可靠性难以满足的情况。仿真结果表明，该文的可靠部署算法在保证可靠性需求的基础上能够有效减少SFC失效损失，同时使虚拟网络更加稳定可靠。

Reliable Deployment Algorithm of Service Function Chain Based on Deep Reinforcement Learning

In view of the current deployment of the Service Function Chain (SFC), the failure importance of the Virtual Network Function (VNF) is not considered,an SFC reliable deployment algorithm based on deep reinforcement learning is proposed. Firstly, a reliable mapping model of VNF and virtual links is establised, high reliability requirements is set for important VNFs, and the reliability requirements of virtual links is ensured as much as possible through link deployment length restrictions. Secondly, taking load balancing as the resource coordination principle, joint optimization the VNF reliability is jointly optimized. Finally, the deep reinforcement learning is used to get the service function chain deployment strategy. In addition, node backup and link backup strategies based on importance are proposed to deal with situations where VNF/link reliability is difficult to meet during deployment. Simulation results show that the reliable deployment algorithm in this paper can effectively reduce the failure SFC loss on the basis of ensuring the reliability requirements, and at the same time make the virtual network more stable and reliable.